1. Field of the Invention
The present invention is in the field of medical devices and more specifically relates to a device that provides a visual indication of whether vials and syringes have been tampered with.
2. The Prior Art
FIG. 1 is an enlarged cross-sectional view through the mouth and neck of a multiple dose vial. Such vials are commonly used to contain injectable mediciments, including narcotics. As shown in FIG. 1, the multiple dose vial includes a glass container 2 whose mouth is sealed by a rubber seal 4 which is pressed against the mouth of the container 2 and held in place by a metal closure 6 that is swaged around the lip 8 of the glass container 2.
In use, fluid is removed from the multiple dose vial of FIG. 1 by inserting the needle of a hypodermic syringe through an aperture 10 in the metal closure 6, through the rubber seal 4 and into the fluid. The fluid is then aspirated into the hypodermic syringe.
FIG. 2 is an enlarged cross-sectional view of the end of a hypodermic syringe cartridge to which the needle is attached. Although the diameter of the cartridge shown in FIG. 2 is somewhat smaller than that of the multiple dose vial of FIG. 1, the structure is quite similar. The cartridge of FIG. 2 typically includes a glass tubular member 12 which terminates in a mouth that is sealed by a rubber seal 14. The rubber seal 14 is pressed in sealing engagement with the mouth of the cartridge by means of a metal closure 16 that is swaged around the lip 18 of the cartridge.
In use, a cap (not shown) including a double-ended hypodermic needle is snaped onto the end of the cartridge shown in FIG. 2. Because of the position of the double-ended needle within the cap, one end of the double-ended needle punctures the rubber seal 14 and extends into the cartridge when the cap is snaped in place. The opposite end of the double-ended needle is used for making the injection.
Both the multiple dose vial of FIG. 1 and the hypodermic syringe cartridge of FIG. 2 may properly be considered to be containers for the fluid that they contain. Frequently, this fluid is a narcotic. Unauthorized persons have been known to insert a hypodermic syringe into such containers to aspirate the narcotic contents, and sometimes a second hypodermic syringe is used to replace the aspirated narcotic with water or a saline solution.
It is difficult to detect whether a multiple dose vial or a hypodermic syringe cartridge has been tampered with in this manner. The rubber seal used in both containers is relatively soft, and when the hypodermic syringe has been removed, it is very difficult to detect visually whether the rubber seal has been punctured.
It is this problem of pilferage of the contents of multiple dose vials and hypodermic syringe cartridges to which the present invention is addressed.